Group Main Line (GML) service created for group clients by operators integrating communication resources provides a brand new portal for corporation communication. With the GML service, a group of clients is provided with a Main Line Number (MLN), and each individual user is allocated an extension number. Meanwhile, various services such as group address book, conference telephone, mobile short-numbers and telephone redirection are integrated, and functions such as service consultation, telephone query, telephone redirection, corporation service, VIP hotline service, main line Color Ring Back Tone (CRBT) are provided to the users.
After a user dials a GML Number (GMLN), operations may be performed under the guidance of voice instructions which include but are not limited to the following.
1. Providing an automatic telephone redirection service if the extension number is dialed or the name of the called party is spoken out directly.
2. Redirecting the call to an attendant for human assistance. The attendant may be provided by the operator renting a helping center to the group of clients, or may be a human main line attendant of the group.
3. Providing corporation services. The call may be redirected to the Customer Service Center of the corporation, or a simple information delivery may be provided by the main line system for the group.
4. Providing a VIP Express Connection to a manager, which connects VIPs of the group to the designated VIP managers.
5. Playing the corporation CRBT after the call to the GML is redirected to the extension, or playing a personal CRBT if the extension is dialed directly.
The manpower cost of a corporation is reduced with the GML, and the labor intensity of the GML attendant is also reduced due to the voice-dialing function.
Currently, there are two solutions for implementing GML service. The first one is based on Intelligent Network (IN), and the second one is based on a value-added voice platform. The major difference between the first solution and second solution is that there is no alternative voice route in the first solution. In other words, the main line platform is no longer ‘bridged’ in the voice route when the call is redirected to the extension, and there is only one voice route from the calling party to the extension, saving a lot of relay resources and improving the security of the main line service system.
FIG. 1 is a diagram illustrating the prior art GML system based on IN. The GML service logic is implemented with an IN Service Control Point (SCP) and an Intelligent Peripheral (IP). The calling process is as follows:
1. A user 11 dials a GMLN;
2. A switch triggers the called process of the GML service to the SCP 10;
3. The SCP 10 issues an Establish Temporary Connection (ETC) signaling instructing the Mobile Switching Center (MSC) 12 to establish a connection to the IP 13;
4. The MSC 12 establishes a connection to the IP 13 through the Gateway Office 14;
5. The IP 13 interacts with the user 11, obtains the extension number to which the user wishes to connect, and submits the extension number to the SCP 10;
6. The SCP 10 issues a Disconnect Forward Connection (DFC) signaling instructing the MSC 12 to tear down the connection to the IP 13;
7. The SCP 10 issues a CONNECT signaling instructing the MSC 12 to connect to the called user 15.
The charging point of the GML service based on IN is the SCP, which generates call records for the calls made from the main line to the extensions and charges the main line.
Currently, for the charging of the extensions in the GML service, the calling charge and called charge for the call between the calling party and the extension user of the GML service are determined according to their respective category tariffs. Assuming that user A calls an MLN B, and then the call is redirected to user C, or user A calls the extension user C directly, the charging principle and call record information for user C is as follows: it is calculated as C answering normally the call from user A, that is, the displayed caller ID is the number of user A. In this case, in the call list of user C, the calling number is that of user A and the called number is that of user C. The communication charge of user C is handled by the charging and accounting system, which collectively processes the call records of user C and rates the call records according to the condition that C is a GML user.
GML provides a corporation with a uniform voice portal and facilitates users internal/external to the corporation. However, with the current charging method, it is impossible to directly control and distinguish the part of charge that is paid collectively by the GML and the part of charge that is paid by the individual. For an extension for which individual payment has already been applied in the operator network before joining the GML, collective payment by the group is applied by the group when the extension joins the GML. For a GML, it is desirable to distinguish the charge of an extension that is paid collectively by the group and the charge of the extension that is paid by the individual, in order to control the communication expense of the GML.